PROFILING OF HOT SURFACES BY PULSED TIME-OF-FLIGHT LASER RANGE FINDERTECHNIQUES

The possibilities for using the pulsed time-of-flight (TOF) laser rada r technique for hot refractory lining measurements are examined, and f ormulas are presented for calculating the background radiation collect ed, the achievable signal-to-noise ratio (SNR), and the measurement re solution. An experimental laser radar device is presented based on the use of a laser diode as a transmitter. Results obtained under real in dustrial conditions show that a SNR of 10 can be achieved at measureme nt distances of up to 15-20 m if the temperature of the converter is 1 400-degrees-C and the peak power of the laser diode used is 10 W. The single-shot resolution is about 60 mm (sigma value), but it can be imp roved to millimeter range by averaging techniques over a measurement t ime of 0.5 s. A commercial laser radar profiler based on the experimen tal laser radar device is also presented, and results obtained with it in real measurement situations are shown. These measurements indicate that it is possible to use the pulsed TOF laser radar technique in de manding measurement applications of this kind to obtain reliable data on the lining wear rate of a hot converter in a steel works.